[Federal Register Volume 59, Number 38 (Friday, February 25, 1994)]
[Unknown Section]
[Page 0]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 94-4372]
[[Page Unknown]]
[Federal Register: February 25, 1994]
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ENVIRONMENTAL PROTECTION AGENCY
40 CFR Part 503
[FRL-4842-8]
Standards for the Use or Disposal of Sewage Sludge
AGENCY: U.S. Environmental Protection Agency (EPA).
ACTION: Final rule.
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SUMMARY: On November 25, 1992, pursuant to section 405 of the Clean
Water Act (CWA), EPA promulgated a regulation to protect public health
and the environment from reasonably anticipated adverse effects of
certain pollutants in sewage sludge (February 19, 1993). This
regulation established requirements for the final use or disposal of
sewage sludge when: (1) The sludge is applied to the land either to
condition the soil or to fertilize crops grown in the soil; (2) the
sludge is disposed on land by placing it in surface disposal sites; and
(3) the sludge is incinerated. Today's action amends this regulation
with respect to two aspects of the rule pending EPA's reconsideration
of certain issues. The issues under reevaluation concern the
appropriate pollutant limits for molybdenum in sewage sludge when land
applied and the requirement for certain sewage sludge incinerators to
monitor incinerator emissions continuously for total hydrocarbons
(THC).
EFFECTIVE DATE: February 19, 1994.
FOR FURTHER INFORMATION CONTACT: Alan Hais, Chief, Sludge Risk
Assessment Branch, Health and Ecological Criteria Division (4304),
Office of Science and Technology, U.S. Environmental Protection Agency,
401 M Street, SW., Washington, DC 20460, telephone (202) 260-5389.
SUPPLEMENTARY INFORMATION:
A. Authority
Today's rule is being promulgated under the authority of section
405 of the Clean Water Act (CWA). Section 405(d) requires EPA to
establish management practices and numerical limits adequate to protect
public health and the environment against reasonably anticipated
adverse effects of toxic pollutants in sewage sludge. Section 405(e)
prohibits any person from disposing of sludge from a publicly-owned
treatment works or other treatment works treating domestic sewage
except in compliance with the section 405 regulations.
B. Amendment of Pollutant Limits for Molybdenum When Land Applied
On November 25, 1992, the U.S. Environmental Protection Agency
promulgated, pursuant to section 405 of the Clean Water Act, Standards
for the Use or Disposal of Sewage Sludge (40 CFR part 503) published in
the Federal Register on February 19, 1993 (58 FR 9248). This regulation
establishes requirements for the final use or disposal of sewage sludge
that are codified at 40 CFR part 503. By letter dated May 25, 1993,
Climax Metals Company filed a petition with the Agency asking that EPA
reconsider the molybdenum pollutant limits for sewage sludge when it is
applied to the land and to stay the February 19, 1994, compliance date
for these pollutant limits pending reconsideration. Subsequently, on
June 25, 1993, Climax Metals Company, American Mining Congress, The
Chem-Met Company, Eastern Technologies, Inc., Gulf Coast Chemical,
Jamestown Chemical Company, Inc., Midland Research Labs, Inc., and
North Metals and Chemical Company, generators or users of molybdenum,
filed a petition with the United States Court of Appeals for the 10th
Circuit seeking review of the land application pollutant limits for
molybdenum in the part 503 Rule. This petition for review was
subsequently transferred to the D.C. Circuit.
The molybdenum cumulative pollutant loading rate (CPLR) promulgated
at Table 2 of Sec. 503.13 in the final part 503 rule is 18 kg of
molybdenum per hectare of land. The CPLR was determined from Pathway 6
of the land application risk assessment. Pathway 6 evaluates the amount
of a pollutant in sewage sludge that is protective of livestock and
wild animals that consume plants grown on sludge-amended soil. In the
case of molybdenum, the CPLR is designed to protect cattle from
molybdenosis. The major concern that Climax and others have brought to
the Agency's attention is related to the studies used to assess
exposure conditions and the exposure assumptions for the establishment
of the molybdenum CPLR for land application of sewage sludge. In
particular, Climax and others questioned the use of the data from the
Pierzynski and Jacobs (1986) study to determine the crop uptake slope
used in the Pathway 6 risk assessment. These interested parties state
that this approach results in an overprotective molybdenum limit
because the sludges used in the study were highly contaminated with
molybdenum (1500 mg molybdenum per kg of sewage sludge, while sewage
sludge usually contains 40 mg/kg) and because the Pierzynski and Jacobs
data were inappropriately weighted with data from only one other study
(Soon and Bates, 1985).
EPA has reviewed Climax's request and has evaluated additional data
and additional information submitted by Climax supporting a different
crop uptake slope for molybdenum. Based on this preliminary evaluation,
EPA is amending part 503 to delete the molybdenum pollutant limits in
Tables 2, 3, and 4 of Sec. 503.13 pending its reconsideration of
appropriate molybdenum pollutant limits. EPA's preliminary review of
the data indicates the appropriateness of reevaluation of the
cumulative pollutant loading rate for molybdenum established in Table 2
of Sec. 503.13 of the February 19, 1993 rule. Because the molybdenum
cumulative pollutant loading rate is used to develop the molybdenum
pollutant concentration limit and annual pollutant loading rate in
Tables 3 and 4 of Sec. 503.13, respectively, EPA is also amending these
tables to remove the molybdenum pollutant limits.
As noted, the molybdenum limits in Tables 2, 3 and 4 were
determined from a risk assessment of Pathway 6 and are designed to
protect animals consuming feed crops grown on sludge-amended soil from
molybdenosis. Specifically, EPA, using a mathematical algorithm,
calculated what quantity of molybdenum in sewage sludge per hectare of
land could be added to the soil without resulting in exceeding the
threshold in crops fed to domesticated animals that is associated with
molybdenosis. That calculation is dependent on three variables. These
are the threshold level of molybdenum in feed crops associated with
molybdenosis, the background level of molybdenum in feed crops and the
relationship between molybdenum added to the soil from sewage sludge
and the resulting level in feed crops.
EPA has reviewed the data it used to establish the molybdenum
limits, information submitted by Climax and others and additional
information the Agency has obtained. EPA has concluded that the
molybdenum limits are highly sensitive to how the molybdenum data base
used in the part 503 regulation was treated. An example illustrates why
the data are sensitive to the method used in the calculation. Assume
that two field studies are used to calculate the uptake of molybdenum
by feed crops grown on sludge-amended soil. One study shows low
molybdenum uptake levels while the second shows high uptake. If the
study with low molybdenum uptake levels includes only three data points
while the study showing high uptake contains 20 data points,
calculation of a single uptake value from the studies will differ
depending on how the data points in the individual studies are treated.
If all data points are weighted equally, then the results will be most
heavily influenced by the high uptake data points. Contrarily, if the
results are averaged for each study separately and then the studies,
rather than data points, weighted equally, the influence of the high
uptake data is mitigated.
Given the limited number of studies relied upon for the part 503
molybdenum limits and the resulting sensitivity of the results to the
method adopted for weighting data points in those studies, EPA
determined that it should reconsider these limits. A preliminary review
of additional field studies suggests that use of data from sewage
sludge that is highly contaminated by molybdenum may yield results that
could overpredict crop uptake and background molybdenum levels in feed
crops at the lower levels of molybdenum required by part 503. This
leads the Agency to conclude that the limits adopted in Tables 2, 3,
and 4 may be more restrictive than required to protect public health
and the environment because of both an inappropriately high background
molybdenum level in feed crops and molybdenum uptake rate. This
information has led the Agency to conclude that it should reevaluate
its determination of the molybdenum pollutant limits for land
application of sewage sludge.
EPA has concluded that amending its regulation to delete the
current land application molybdenum pollutant limits pending
reconsideration will not adversely affect public health and the
environment for the following reasons. First, EPA is not modifying the
ceiling concentration limit for molybdenum (75 milligrams per kilogram
of sewage sludge on a dry weight basis) in Table 1 of Sec. 503.13.
Sewage sludge that is land applied must have a molybdenum concentration
equal to or less than this limit. Sewage sludge that exceeds this level
cannot be land applied. Under a worst case scenario of 75 milligrams of
molybdenum per kilogram of dry sewage sludge, if sewage sludge is
applied at a rate of 10 metric tons of sewage sludge (dry weight basis)
per hectare of land annually, it would take 24 years to reach the
cumulative pollutant load of 18 kilograms per hectare for molybdenum--
the CPLR adopted in Table 2 of Sec. 503.13 in the final rule. Because
EPA plans to propose and promulgate a new molybdenum cumulative
pollutant loading rate in the near future, a new molybdenum pollutant
concentration limit and a new annual pollutant loading rate (APLR),
even if EPA concludes the same or lower limits are necessary to protect
public health and the environment, the likelihood that the molybdenum
in sewage sludge applied to the land during the time EPA reevaluates
the molybdenum CPLR would harm public health and the environment is
extremely low.
Similarly, under this worst case scenario, sewage sludge sold or
given away in a bag or other container for application to the land
(e.g., for use on lawns or home gardens) is limited to an annual
application rate of 12 dry metric tons per hectare. This application
rate is calculated based on the ceiling concentration of 75 mg
molybdenum per kg of dry sewage sludge and the annual pollutant loading
rate of 0.9 kg per hectare per 365 day period listed in Table 4 of
Sec. 503.13. Application rates above this amount would cause an
exceedence of the molybdenum annual pollutant loading rate. However,
the molybdenum pollutant limit on which the APLR is based is designed
to protect animals consuming forage grown on sludge amended soils from
molybdenum toxicity. The likelihood of cattle consuming feed crops
grown on a lawn or home garden is small. In the multi-pathway risk
assessment, the next most limiting pathway for molybdenum is Pathway 3,
the ingestion of pure sewage sludge by a toddler. Pathway 3 is a more
realistic concern for sewage sludge sold or given away in a bag or
other container. The pollutant limit for this pathway is 400 milligrams
of molybdenum per kilogram of dry sewage sludge, well above the ceiling
concentration limit of 75 mg molybdenum per kg of dry sewage sludge.
Because sewage sludge cannot be applied to the land if the molybdenum
concentration is greater than 75 mg molybdenum per kg of dry sewage
sludge, the toddler who may inadvertently ingest sewage sludge is
protected during the time the Agency reconsiders the molybdenum
pollutant limits. Therefore, today's amendments to the pollutant limits
in Tables 2, 3, and 4 of Sec. 503.13 will not threaten public health or
the environment for land application of either bulk sewage sludge sold
or sewage sludge sold or given away in a bag or other container.
C. Modification of the Applicability of the Continuous Emission
Monitoring Requirements for Total Hydrocarbons for Certain Incinerators
On July 17, 1993, Gloucester County Utilities, Stony Brook Regional
Sewerage Authority, Township of Wayne, Pequannock, Lincoln Park and
Fairfield Sewerage Authority, Somerset Raritan Valley Sewerage
Authority, Bayshore Regional Sewerage Authority, and the State of New
Jersey filed a petition with the D.C. Circuit seeking review of the
part 503 regulation. These petitioners challenged, among other things
the failure of the part 503 regulation to allow site-specific sewage
sludge incinerator emissions limits and the failure to allow State-
imposed emissions limitations, including monitoring and reporting
requirements, to replace the part 503 requirements. The petitioners
argue that the requirements to demonstrate compliance with a 100 ppm
total hydrocarbon (THC) operational standard through continuous
monitoring of THC emissions should be changed.
Currently, the State of New Jersey requires that the exit gas from
the petitioners' sewage sludge incinerators meet a 100 ppm carbon
monoxide (CO) limit corrected for zero percent moisture and to seven
percent oxygen. The State also requires the petitioners to monitor the
exit gas continuously for CO. For these reasons, the petitioners asked
for relief from the requirement to monitor THC continuously. To
demonstrate compliance with the 100 ppm THC operational standard, the
incinerator management practices in Sec. 503.45(a) require installation
of a continuous equipment THC monitor. In the petitioners' view,
installation of this instrument is not needed because any sewage sludge
incinerator complying with State of New Jersey 100 ppm emissions
limitation and continuous CO monitoring requirements will comply with
the 100 ppm THC operational standard.
EPA concluded that it is appropriate to reconsider its requirement
for the continuous monitoring of THC in the case of certain
incinerators. Based on a reassessment of information on THC emissions
and CO emissions from certain types of sewage sludge incinerators, EPA
has preliminary determined that incinerators that meet a 100 ppm CO
emission limitation will easily achieve a 100 ppm THC operational
standard. In these circumstances, EPA determined that requiring such
incinerators to install and maintain continuous THC monitors was unduly
burdensome and wasteful and would not result in increased environmental
benefits. Accordingly, EPA finds there is good cause to amend its
regulation, effective immediately, to authorize the demonstration of
compliance with the 100 ppm THC operational standard by meeting a 100
ppm CO limit and by monitoring the exit gas continuously for CO during
the interim period of reconsideration. Therefore, EPA is today issuing
a final rule amending the applicability provision of the part 503--
subpart E--Incineration to modify the applicability of certain
management practices, frequency of monitoring requirements and
recordkeeping requirements for sewage sludge incinerators meeting
certain conditions.
As a result of the amendment, the following requirements will not
apply to sewage sludge incinerators meeting defined conditions: the
management practice in Sec. 503.45(a); the frequency of monitoring
requirements for THC concentration in Sec. 503.46(b); and the
recordkeeping requirements for THC concentration in Sec. 503.47 (c) and
(n). The management practice in 503.45(a) requires the installation of
a continuous emissions monitor for total hydrocarbons. The monitoring
requirements of Sec. 503.46(b) concern THC concentration in the exit
gas. The recordkeeping requirements in Sec. 503.47 (c) and (n) deal
with the total hydrocarbons concentration in the exit gas from the
sewage sludge incinerator stack and with a calibration and maintenance
log for THC concentration in the exit gas.
The requirements outlined above do not apply to sewage sludge
incinerators in the following circumstances. The sewage sludge
incinerator must achieve a CO concentration in the exit gas of 100 ppm
(monthly average) or lower, corrected for zero percent moisture and to
seven percent oxygen. The incinerator owner/operator also must monitor
the exit gas continuously for CO, keep records on the CO emissions,
and, in certain cases, report the monthly average CO concentration
annually to the permitting authority.
EPA concluded there is good cause for taking today's action because
current data support the petitioners' assertion that the THC
concentration in the exit gas from the sewage sludge incinerators
described above will comply with the 100 ppm (monthly average) THC
operational standard in part 503 when the monthly average CO
concentration in the exit gas is equal to or less than 100 ppm.
D. Procedural Requirements
EPA has reviewed the two requests discussed above and concluded
that: (1) The molybdenum CPLR, pollutant concentration limit, and APLR
for land application should be reconsidered based on the new
information, and (2) the THC operational standard in Sec. 503.44(c)
will be achieved if a CO limit of 100 ppm is met. Accordingly, EPA is
today taking final action amending its part 503 regulation. EPA's
action amends the molybdenum pollutant limits for land application in
Tables 2, 3, and 4 of Sec. 503.13 and the applicability of various part
503 requirements related to THC in Sec. 503.45, Sec. 503.46, and
Sec. 503.47 for certain incinerators until such time as the Agency has
an opportunity to study these issues further. At the completion of the
studies, EPA will decide whether to propose new molybdenum pollutant
limits and whether further amendments to part 503 are needed concerning
the monitoring of CO to demonstrate compliance with the THC operational
standard in lieu of monitoring THC continuously.
Section 553 of the Administrative Procedures Act provides that when
an agency for good cause finds that notice and public procedure are
impracticable, unnecessary or contrary to the public interest, it may
first issue a rule without providing notice and comment. In addition,
the agency may make the rule effective immediately. EPA has concluded
here that it should both amend its part 503 regulation as described
without providing for notice and comment and make these changes
effective immediately.
1. Notice and Comment
By today's action, the Agency avoids the possibility that some
treatment works treating domestic sewage would be required to comply
with certain numerical limits for molybdenum in sewage sludge that is
land applied. The Agency has concluded at this juncture that these
limits may be too stringent and consequently should be reconsidered.
Given the pendency of the compliance deadline for the land application
requirements, it would be impracticable to provide notice and comment.
Further, the public interest would suffer to the extent that treatment
works treating domestic sewage incurred increased costs associated with
compliance with requirements that the Agency determines are not needed
to protect public health and the environment. Given the retention of
the ceiling limit on molybdenum in sewage sludge which may be applied
to the land, EPA has concluded that public health and the environment
will be adequately protected while the Agency is reconsidering what are
the appropriate molybdenum limits for Tables 2, 3 and 4 of Sec. 503.13.
Further, in the case of the amendments to the requirements for
sewage sludge incinerators, the Agency has similarly concluded that
notice and comment is impracticable and contrary to the public
interest. EPA has concluded that the public interest will suffer if
sewage sludge incinerators that achieve a 100 ppm CO level, as
demonstrated by continuous CO monitoring, are also required to install
THC monitors. Based on its evaluation, EPA has concluded that, if
incinerators are meeting a 100 ppm CO level, the likelihood is
substantial that such incinerators are well below the 100 ppm THC
operational standard. Given this information and the fact that the
obligation for many of these incinerators to achieve a 100 ppm or lower
CO standard and monitor continuously antedated the promulgation of the
100 ppm THC operational standard, EPA has concluded that the public
interest does not support installation of THC monitors for such
incinerators pending Agency reconsideration.
2. Effective Date
Under section 405 of the CWA, EPA's sewage sludge regulation must
require compliance with the regulation as expeditiously as practicable
but in no case later than 12 months after its publication, unless such
regulation requires construction of new pollution control facilities,
in which case the regulation must require compliance expeditiously, but
not later than two years from publication. The part 503 regulation was
effective on March 22, 1993. In the case of the molybdenum pollutant
limits and the continuous monitoring requirements for THC, the
regulation required compliance by February 19, 1994. Because of the
potential adverse effect on public interest noted above, the Agency has
determined there is good cause for making this regulation effective
immediately.
E. Regulatory Requirements
1. Executive Order 12866
Executive Order 12866 requires EPA to prepare an assessment of the
costs and benefits of any ``significant regulatory action.'' Because
the effect of today's rule is to modify current requirements and
provide additional flexibility to the regulated community, costs to the
regulated community should be reduced or at least remain unchanged.
Consequently, no assessment of costs and benefits is required.
2. Regulatory Flexibility Act
Pursuant to the Regulatory Flexibility Act, 5 U.S.C. 601-612,
whenever an agency is required to publish a General Notice of
Rulemaking for any proposed or final rule, it must prepare and make
available for public comment a regulatory flexibility analysis that
describes the impact of the rule on small entities (i.e., small
businesses, small organizations, and small governmental jurisdictions).
No regulatory flexibility analysis is required, however, if the head of
the Agency certifies that the rule will not have a significant impact
on a substantial number of small entities.
This action to modify the part 503 regulation promulgated today is
deregulatory in nature and thus will only provide beneficial
opportunities for entities that may be affected by the rule.
Accordingly, I certify that this regulation will not have a significant
economic impact on a substantial number of small entities. This
regulation, therefore, does not require a regulatory flexibility
analysis.
3. Paperwork Reduction Act
There are no reporting, notification, or recordkeeping
(information) provisions in this rule. Such provisions, were they
included, would be submitted for approval to the Office of Management
and Budget (OMB) under the Paperwork Reduction Act, 44 U.S.C. 3501 et
seq.
List of Subjects in 40 CFR Part 503
Environmental protection, Frequency of monitoring, Incineration,
Land application, Management practices, Pathogens, Pollutants,
Reporting and recordkeeping requirements, Sewage sludge, Surface
disposal and Vector attraction reduction.
Dated: February 18, 1994.
Carol M. Browner,
Administrator.
For the reasons set out in the preamble, part 503 of title 40 of
the Code of Federal Regulations is amended as set forth below:
1. The authority citation for part 503 continues to read as
follows:
Authority: Sections 405 (d) and (e) of the Clean Water Act, as
amended by Pub. L. 95-217, Sec. 54(d), 91 Stat. 1591 (33 U.S.C. 1345
(d) and (e)); and Pub. L. 100-4, Title IV, Sec. 406 (a), (b), 101
Stat., 71, 72 (33 U.S.C. 1251 et seq.).
2. Section 503.13 is amended by revising paragraphs (b)(2), (b)(3),
and (b)(4) to read as follows:
Sec. 503.13 Pollutant limits.
(b) * * *
(2) Cumulative pollutant loading rates.
Table 2 of Sec. 503.13.--Cumulative Pollutant Loading Rates
------------------------------------------------------------------------
Cumulative
pollutant
loading
Pollutant rate
(kilograms
per
hectare)
------------------------------------------------------------------------
Arsenic.................................................... 41
Cadmium.................................................... 39
Chromium................................................... 3000
Copper..................................................... 1500
Lead....................................................... 300
Mercury.................................................... 17
Nickel..................................................... 420
Selenium................................................... 100
Zinc....................................................... 2800
------------------------------------------------------------------------
(3) Pollutant concentrations.
Table 3 of Sec. 503.13.--Pollutant Concentrations
------------------------------------------------------------------------
Monthly
average
Pollutant concentrations
(milligrams
per kilogram)1
------------------------------------------------------------------------
Arsenic................................................. 41
Cadmium................................................. 39
Chromium................................................ 1200
Copper.................................................. 1500
Lead.................................................... 300
Mercury................................................. 17
Nickel.................................................. 420
Selenium................................................ 36
Zinc.................................................... 2800
------------------------------------------------------------------------
1Dry weight basis.
(4) Annual pollutant loading rates.
Table 4 of Sec. 503.13.--Annual Pollutant Loading Rates
------------------------------------------------------------------------
Annual
pollutant
loading rate
Pollutant (kilograms
per hectare
per 365 day
period)
------------------------------------------------------------------------
Arsenic................................................... 2.0
Cadmium................................................... 1.9
Chromium.................................................. 150
Copper.................................................... 75
Lead...................................................... 15
Mercury................................................... 0.85
Nickel.................................................... 21
Selenium.................................................. 5.0
Zinc...................................................... 140
------------------------------------------------------------------------
* * * * *
5. Section 503.40 is amended by adding paragraph (c) to read as
follows:
Sec. 503.40 Applicability.
* * * * *
(c) The management practice in Sec. 503.45(a), the frequency of
monitoring requirement for total hydrocarbon concentration in
Sec. 503.46(b) and the recordkeeping requirements for total hydrocarbon
concentration in Sec. 503.47(c) and (n) do not apply if the following
conditions are met:
(1) The exit gas from a sewage sludge incinerator stack is
monitored continuously for carbon monoxide.
(2) The monthly average concentration of carbon monoxide in the
exit gas from a sewage sludge incinerator stack, corrected for zero
percent moisture and to seven percent oxygen, does not exceed 100 parts
per million on a volumetric basis.
(3) The person who fires sewage sludge in a sewage sludge
incinerator retains the following information for five years:
(i) The carbon monoxide concentrations in the exit gas; and
(ii) A calibration and maintenance log for the instrument used to
measure the carbon monoxide concentration.
(4) Class I sludge management facilities, POTWs (as defined in 40
CFR 501.2) with a design flow rate equal to or greater than one million
gallons per day, and POTWs that serve a population of 10,000 people or
greater submit the monthly average carbon monoxide concentrations in
the exit gas to the permitting authority on February 19 of each year.
[FR Doc. 94-4372 Filed 2-24-94; 8:45 am]
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